14 February 1992 Review of filtering methods in mobile vision from ground vehicles in low light conditions
Author Affiliations +
Proceedings Volume 1613, Mobile Robots VI; (1992) https://doi.org/10.1117/12.135191
Event: Robotics '91, 1991, Boston, MA, United States
We discuss the application of nonlinear median, alpha-trimmed mean filters and moving average to images from an intensified CCD camera which is mounted inside a vehicle on the dashboard. Discrete filtering strategies based on alpha-trimmed mean as a prefilter to prepare an image to automatic moving average has been done. In fact, the smoothing characteristics of the order statistics filters and the integrated value of the moving average have been combined to produce a good-looking image to the human eye. In some cases, an object shape isn't completely defined in the new image after the filters have been applied. In these cases resulting from poor acquisition due to subexposition or intensive shading, a histogram modification has been effected. The intensified camera system performs at light levels as low as 0.0001 lux, equivalent to an overcast moonless night. The regular CCD cameras operate in light levels of around 0.1 lux, scene illumination at least equivalent to the light on a full moonlit night. We show, through a series of examples, that these filters can be effectively used to partially eliminate veiling glare effect and brightness fluctuation with time, which comprise the most significant noise in an intensifier tube application.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Cassiano Paixao Pais, Cassiano Paixao Pais, Fernando D. Carvalho, Fernando D. Carvalho, Fernando Carvalho Rodrigues, Fernando Carvalho Rodrigues, Mateus da Silva, Mateus da Silva, "Review of filtering methods in mobile vision from ground vehicles in low light conditions", Proc. SPIE 1613, Mobile Robots VI, (14 February 1992); doi: 10.1117/12.135191; https://doi.org/10.1117/12.135191

Back to Top